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Diagnostics

P0402 points to EGR flow above the expected amount

Too much detected flow can affect idle quality, but the code itself does not prove a stuck valve.

Topics

#egr#emissions#p0402
September 25, 20261 min read
AI4Car quick readA short, original guide from the AI4Car knowledge library.

Compare commanded position with feedback and check for a valve that does not respond as expected. Use the exact service procedure before cleaning or replacing parts.

Quick educational note

For information, not a diagnosis or repair instruction. Vehicle-specific checks are still required. Consult the manufacturer's guidance and a qualified technician.

How to use this information

This article explains general principles and does not establish what is wrong with your vehicle. Read the content limitations.

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P0402 points to EGR flow above the expected amount | AI4Car